Automatic chuck.



No. 790,656. I v PATENTED MAY/23, 1.905. J. PEARSON.

AUTOMATIC CHUCK. APPLICATION FILED 0UT.12, 1903.

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UNIT D STATES Patented May 23, 1905.

PATENT OFFICE.

JAMES PEARSON, OF CLEVELAND, OHIO, ASSIGNOR TO THE WARNER AND SWASEY 00., OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

AUTOMATIC CHUCK.

sPEcIIsIcATIon forming part of Letters Patent No. 790,656, dated May '23, 1905.

Application filed October 12,1903. Serial No. 176,621.

To all whom it near concern.-

Be it known that I, J AMES PEARSON, aoitizen of the United States, residing at Cleveland, in the county of Ouyahoga and State of Ohio, have invented a certain new and useful Improvement in Automatic Chucks, of which the following is a full, clear, and exact description, reference being had to the accompanying'drawings.

Automatic chucks such as have been in common use for many years have certain characteristics which are in the nature of deacteristic is the liability of the spring-jaws to break. Another undesirable characteristic is that it is necessary to almost dismantle and rebuild the front end of the live-spindle in order to adapt the same for stock rods of larger or smaller diameter. Another defect is that if the stock rods being worked are not exactly uniform in diameter the length of rod which projects beyond the chuck-jaws after they have firmly grasped it is not always the same.

The object of this invention is to provide a chuck which is durable, in which the jaws are easily removable and replaceable, and which hacxl e no endwise motion as they grip the stock r0 The invention, which is illustrated in the drawings and hereinafter described, may be here summarized as consisting in the construction and combination of parts definitely set forth inthe claims.

In the drawings, Figure 1 is a longitudinal centra section of the front end of a live-spindle containing my invention. Fig. 2 is a transverse section in the planeindicated by line 2 2 of Fig. 1 and Fig. 3 is a detached View of the sleeve E.

Referring to the parts by letters, A represents the tubular live-spindle of a screw-machane, turret-lathe, or the like. Within this spindle is the longitudinal movable tube O, common in devices of this character, the function of which is to cause the operation of the 'compression member B by its forward movement in the spindle. The compression member B is a tube which is fitted into the spin- Perhaps the most objectionable chardle and is capable. of being moved endwise therein by the endwise movement of said tube 0. The front end of the tube B is conically fiaringthat is to say, it is internally tapered and is largest at its front end. It may be prevented from rotating within the spindle by ascrew F, which enters a longitudinal slot in the tube B, and thereby does not interfere with the longitudinal movement of said tube. Within the fiaring front end of the tube Bare four, more or less, independent chuck-jawsD, whichjaws-externally are tapered to substantially fit the tapered interior of the tube B. These jaws are of segmental form of such width that they do not entirely complete the circle when in place, as shown. In their proximate edges are longitudinal slots d, which extend from their rear ends forward. A sleeve E is fitted within the tube B, and it has forwardly-projecting springarms a, which enter the groove d of two adjacent chuck-jaws. These arms prevent the jaws from falling inward and, in fact, by their spring action hold them in contact with the flaring inner surface of the tube B. The front end of this sleeve E abuts against the rear end of the jaws. A ring Gr screws into the front end of the spindle and abuts the annular shoulders d on the chuck-jaws, and thus prevents them from coming out of the spindle. A coiled spring K is placed within the tube B, and it exerts its force against the rear end of the sleeve E and an internal flange b on the tube B. The result is that the sleeve E is forced forward, and it in turn forces the chuck-jaws forward into contact with the ring G, and this spring also forces the tube B rearward, so as to allow the chuck-jaws to expand to their fullest capacity.

7 The stock rod is fed forward through the tubes O and B and the sleeve E and chuckjaws. When it projects far enough, the tube C is moved forward in the spindle by any suitable instrumentalityas, for example, the fingers commonly employed for this purpose. The tube B is thereby moved forward, with the result of causing the chuck-jaws to contract upon the stock rod and to hold it firmly. When it is desired to release the stock rod,

the tube 0 is allowed to move rearward, whereupon the spring K moves the tube B rearward, thereby allowing the chuck-jaws to open. When it is desired to adapt the spindle for stock rods of different diameter, it is only necessary to unscrew the ring G and to substitute chuck-jaws of less or greater thickness, so that the internal diameter of the space inside said jaws shall be greater or less, as desired.

Having described my invention, 1 claim- 1. The combination, with the tubular livespindle of a screw-machine or the like, of a plurality of independent segmental chuckjaws having tapered exterior surfaces and having longitudinal grooves in their proximate edges extending from their rear ends forward, means preventing the forward movement of said chucking-jaws, a tube within said spindle which abuts the rear end of said jaws and has forwardly-projecting arms which enter said slots, a longitudinally-movable compression-tube which embraces and extends rearward beyond the tube first named and has a flaring front end which embraces'said jaws, and an inwardly-turned flange on its rear end, a spring compressed between said flange and the rear end of the arm carrying the tube.

2. The combination, with the tubular livespindle of a screw-machine or the like, of a plurality of independent segmental chuckjaws having outwardly-extended flanges near their front ends, and, behind them, tapered convex exterior surfaces, and longitudinal slots in their proximate edges, a ring which screws into the end of the spindle against the shoulders on said jaws, a longitudinally-movable compression member within said spindle having a flaring front end which embraces said jaws, a tube within said compression member having forwardly-extended springarms which enter the slots in the edges of said jaws, means preventing the rotation of said compression member, and a spring acting to move the compression member rearward and said tube forward.

3. The combination, with the tubular livespindle of a screw-machine or the like, a plurality of segmental chuck-jaws having recesses which open from their rear ends, a tube within the spindle having forwardly-pr0jeeting spring-arms which enter said recess and prevent the jaws from falling inward, and a compression member for forcing said jaws inward.

4. The combination, with the tubular li\'e spindle of a screw-machine or the like, of a plurality of segmental chuck-jaws having longitudinally-grooved proximate edges, a tube within the spindle having forwardly-projeeting arms which span the intervals between said jaws and project into said grooves, and mechanism for forcing said jaws inward.

In testimony whereof I hereunto allix my signature in the presence of two witnesses.

JAMES PEARSON.

\Vitnesses:

V. M. ALLEN, JOHN WEBER. 

